standard instrumentation JFET op-amps fo EEG?

prof_braino

Another inspiring Ted Talk

http://www.ted.com/talks/tan_le_a_headset_that_reads_your_brainwaves.html

has gotten me interested in tan_le's headset_that_reads_your_brainwaves. Unfortunately, at $500 it's about $500 too expensive for me at the moment.

This does not use paste or gel nor does it require abrading the skin. How the heck to they do that? The suggestion was JFET op-amps used as standard instrumentation amp, just configure the op-amp to have a very high impedance. I've heard of op amps but this is all greek to me. Anybody interested in figuring out the sensors for this?

The hard part is the algorithm that flattens out the folds of the cortex and maps them. But that's for later. There a bunch of papers at the Emotiv website, but they are little deep for me.

http://www.emotiv.com/researchers/

GordonMcComb

There's always this as a fall back:

http://www.amazon.com/Mattel-P2639-Mindflex-Game/dp/B001UEUHCG

From the descriptions, the sensor reads activity in the front lobe. As I've had mine removed (something about not wanting to risk another homicidal episode), the sensing won't work for me. You might have better luck.

-- Gordon

prof_braino

Yeah, that was what peaked my interest a while back. I'm interested in what the sensors are and how they work. I think the op amps and circuit would be less than 53 buck?

Anybody know what EEG sensors look like on the inside? Are those just conductive foam?

Leon

When I was involved with that stuff we used silver-silver chloride electrodes.

Bob Lawrence (VE1RLL)

@ prof_braino

http://www.ti.com/lit/ds/symlink/tlc272.pdf

http://www.bioera.net/bw/ae/active_prototype2.html

http://openeeg.sourceforge.net/doc/hw/electrodes/

prof_braino

Thanks Bob! That's exactly what I was looking for. I'm off to a good start.

prof_braino

@Leon - Any details on instrumentation and algorithms? My guess is that is pretty much the same, and the new part is Tan Le's algorithm for ironing out the creases of the cortex.